Water purification technology is rapidly becoming an essential aspect of modern life as conventional water resources become increasingly scarce, municipal distribution systems for potable water deteriorate with age, and increased water usage depletes wells and reservoirs, causing saline water contamination. Additionally, further contamination of water sources is occurring from a variety of activities, which include, for example, intensive agriculture, gasoline additives, and heavy toxic metals. These issues are leading to increasing and objectionable levels of germs, bacteria, salts, MTBE, chlorates, perchlorates, arsenic, mercury, and even the chemicals used to disinfect potable water, in the water system.
Conventional technologies, such as reverse osmosis (RO), filtration, and chemical treatment are rarely able to handle the diverse range of water contaminants. Additionally, even though they are commercially available, they often require multiple treatment stages or combination of various technologies to achieve acceptable water quality. Less conventional technologies, such as ultraviolet (UV) light irradiation or ozone treatment, can be effective against viruses and bacteria, but seldom remove other contaminants, such as dissolved gases, salts, hydrocarbons, and insoluble solids. Additionally, most distillation technologies, while they may be superior at removing a subset of contaminants are frequently unable to handle all types of contaminants.
Accordingly, sophisticated distillation systems that are continuous, self-cleaning, and recover a major fraction of the input water appear as the best long-term option to resolve increasing water contamination problems and water scarcity.